Abstracto

Prediction &Control of Chatter in Milling Machine Spindle-Tool Unit -A Review

Sunilsing Rajput, Dr. D.S. Deshmukh

Chatter is a self-excited vibration which occurs in milling machines while operating at high speed. This is an undesirable phenomenon which has negative effects, such as poor surface finish, unacceptable accuracy, excess noise, tool wear and lower Material Removal Rate (MRR). Chatter is self-excited vibration which can occur by various phenomenon’s like Frictional chatter, thermo-mechanical chatter, Mode Coupling Chatter and very importantly regenerative chatter. Prediction and detection of chatter is very important in milling machine tool, which gives guidance to the machine tool user for an optimal selection of depth of cut and spindle speed, which results in higher material removal rate with high accuracy, with less vibrations. Chatter prediction is very complicated phenomenon in machine for its avoidance. In this paper, various methods are presented for the prediction of chatter. Analytical and experimental methods are presented in this paper for the chatter control which gives idea for the selection of optimal speed and depth of cut from the stability lobe diagram (SLD) and easiest method for chatter prediction is suggested. Stability lobe diagram is an effective tool which helps the operator to select specific spindle speeds for avoidance of chatter in machine. Stability lobes are plotted against axial depth of cut vs. spindle speed, which shows a boundary between stable and unstable regions.